Biological Invasions

, Volume 13, Issue 3, pp 635–650 | Cite as

Comparative phylogeography of two colonial ascidians reveals contrasting invasion histories in North America

  • Christophe Lejeusne
  • Dan G. Bock
  • Thomas W. Therriault
  • Hugh J. MacIsaac
  • Melania E. Cristescu
Original Paper


Surveys of genetic structure of introduced populations of nonindigenous species may reveal the source(s) of introduction, the number of introduction events, and total inoculum size. Here we use the mitochondrial cytochrome c oxidase subunit 1 (COI) gene to explore genetic structure and contrast invasion histories of two ecologically similar and highly invasive colonial ascidians, the golden star tunicate Botryllus schlosseri and the violet tunicate Botrylloides violaceus, in their global and introduced North American ranges. Haplotype and nucleotide diversities for B. schlosseri were significantly higher than for B. violaceus both globally (h = 0.872; π = 0.054 and h = 0.461; π = 0.007, respectively) and in their overlapping North American ranges (h = 0.874; π = 0.012 and h = 0.384; π = 0.006, respectively). Comparative population genetics and phylogenetic analyses revealed clear differences in patterns of invasion for these two species. B. schlosseri populations on the west and east coasts of North America were seeded from the Pacific and Mediterranean regions, respectively, whereas all North American B. violaceus populations were founded by one or more introduction events from Japan. Differences in genetic structure of invasive populations for these species in North America are consistent with their contrasting probable introduction vectors. B. schlosseri invasions most likely resulted from vessel hull fouling, whereas B. violaceus was likely introduced as a ‘fellow traveler’ in the shellfish aquaculture trade.


Nonindigenous species Mitochondrial DNA Introduction Tunicates Botryllus schlosseri Botrylloides violaceus 



We acknowledge our Canadian Aquatic Invasive Species Network (CAISN) colleagues G. Arsenault, J. Davidson, J. Hill, and A. Ramsay as well as our global colleagues T. Bolton, P. Chevaldonné, R. Graille, E. Grey, A. Izquierdo-Munoz, B. de Ligondes, S. Lopez-Legentil, J.-M. Nicolas, M. Ruis-Viladomiu, Y. Saito, X. Turon, and B. Vercaemer, who have so generously provided tunicate samples. D. Heath, S. Xu and A. Zhan provided valuable comments on an early draft of the manuscript. We also thank A. Adebayo, K. Laroche and R. Hepburn for assisting with lab work. This work was supported by CAISN, Fisheries and Oceans Canada and by NSERC Discovery grants to MEC and HJM.

Supplementary material

10530_2010_9854_MOESM1_ESM.doc (132 kb)
Supplementary material 1 (DOC 132 kb)


  1. Avise JC, Arnold J, Ball RM, Bermingham E, Lamb T, Neigel JE, Reeb CA, Saunders NC (1987) Intraspecific phylogeography: the mitochondrial DNA bridge between population genetics and systematics. Annu Rev Ecol Syst 18:489–522Google Scholar
  2. BCMAL (2007) Shellfish aquaculture: current statistics. British Columbia Ministry of Aquaculture and Lands, BC, 108 ppGoogle Scholar
  3. Ben-Shlomo R, Paz G, Rinkevich B (2006) Postglacial-period and recent invasions shape the population genetics of botryllid ascidians along European Atlantic coasts. Ecosystems 9:1118–1127CrossRefGoogle Scholar
  4. Berril NJ (1950) The Tunicata, with an account of British species. Ray Society, London, iii+354ppGoogle Scholar
  5. Brunetti R, Beghi L, Bressan M, Marin MG (1980) Combined effects of temperature and salinity on colonies of Botryllus schlosseri and Botrylloides leachi (Ascidiacea) from the Venetian Lagoon. Mar Ecol Prog Ser 2:303–314CrossRefGoogle Scholar
  6. Carlton JT (1989) Man’s role in changing the face of the ocean: biological invasions and implications for conservation of near-shore environments. Conserv Biol 3:265–266CrossRefGoogle Scholar
  7. Carlton JT (2005) Setting ascidian invasions on the global stage. International Invasive Sea Squirt Conference. Woods Hole Oceanographic Institution, Woods HoleGoogle Scholar
  8. Carlton JT, Geller JB (1993) Ecological roulette—the global transport of nonindigenous marine organisms. Science 261:78–82CrossRefGoogle Scholar
  9. Carver CE, Mallet AL, Vercaemer B (2006) Biological synopsis of the colonial tunicates, Botryllus schlosseri and Botrylloides violaceus. Canadian Manuscript Report of Fisheries and Aquatic Sciences 2747: v+42pGoogle Scholar
  10. Castilla JC, Guinez R, Caro AU, Ortiz V (2004) Invasion of a rocky intertidal shore by the tunicate Pyura praeputialis in the Bay of Antofagasta, Chile. Proc Natl Acad Sci 101:8517–8524CrossRefPubMedGoogle Scholar
  11. Clement M, Posada D, Crandall KA (2000) TCS: a computer program to estimate gene genealogies. Mol Ecol 9:1657–1659CrossRefPubMedGoogle Scholar
  12. Cohen AN, Carlton JT (1995) Biological study. Nonindigenous aquatic species in a United States estuary: a case study of the biological invasions of the San Francisco Bay and Delta. A report for the US Fish and Wildlife Service and National Sea Grant College Program. National Technical Information Service, Springfield, p 246Google Scholar
  13. Colautti RI, MacIsaac HJ (2004) A neutral terminology to define ‘invasive’ species. Divers Distrib 10:135–141CrossRefGoogle Scholar
  14. Colautti RI, Manca M, Viljanen M, Ketelaars HAM, Burgi H, MacIsaac HJ, Heath DD (2005) Invasion genetics of the Eurasian spiny waterflea: evidence for bottlenecks and gene flow using microsatellites. Mol Ecol 14:1869–1879CrossRefPubMedGoogle Scholar
  15. Coutts ADM, Dodgshun TJ (2007) The nature and extent of organisms in vessel sea-chests: a protected mechanism for marine bioinvasions. Mar Pollut Bull 54:875–886CrossRefPubMedGoogle Scholar
  16. Crandall KA (1996) Multiple interspecies transmissions of human and simian T-cell leukemia/lymphoma virus type I sequences. Mol Biol Evol 13:115–131PubMedGoogle Scholar
  17. Cristescu MEA, Hebert PDN, Witt JDS, MacIsaac HJ, Grigrovich IA (2001) An invasion history for Cercopagis pengoi based on mitochondrial gene sequences. Limnol Oceanogr 46:224–229CrossRefGoogle Scholar
  18. Deangelis MM, Wang DG, Hawkins TL (1995) Solid-phase reversible immobilization for the isolation of PCR products. Nucleic Acids Res 23:4742–4743CrossRefPubMedGoogle Scholar
  19. Dijkstra J, Harris LG, Westerman E (2007) Distribution and long-term temporal patterns of four invasive colonial ascidians in the Gulf of Maine. J Exp Mar Biol Ecol 342:61–68CrossRefGoogle Scholar
  20. Drake JM, Lodge DM (2004) Global hot spots of biological invasions: evaluating options for ballast-water management. Proc R Soc Lond Ser B Biol Sci 271:575–580CrossRefGoogle Scholar
  21. Dupont L, Viard F, Dowell MJ, Wood C, Bishop JDD (2009) Fine- and regional-scale genetic structure of the exotic ascidian Styela clava (Tunicata) in southwest England, 50 years after its introduction. Mol Ecol 18:442–453CrossRefPubMedGoogle Scholar
  22. Elphinstone MS, Hinten GN, Anderson MJ, Nock CJ (2003) An inexpensive and high-throughput procedure to extract and purify total genomic DNA for population studies. Mol Ecol Notes 3:317–320CrossRefGoogle Scholar
  23. Epelbaum A, Herborg LM, Therriault TW, Pearce CM (2009) Temperature and salinity effects on growth, survival, reproduction, and potential distribution of two non-indigenous botryllid ascidians in British Columbia. J Exp Mar Biol Ecol 369:43–52CrossRefGoogle Scholar
  24. Excoffier L, Smouse PE, Quattro JM (1992) Analysis of molecular variance inferred from metric distances among DNA haplotypes: application to human mitochondrial DNA restriction data. Genetics 131:479–491PubMedGoogle Scholar
  25. Excoffier L, Laval G, Schneider S (2005) Arlequin ver. 3.0: an integrated software package for population genetics data analysis. Evol Bioinform Online 1:47–50PubMedGoogle Scholar
  26. Fay RC, Vallee JA (1979) A survey of the littoral and sublittoral ascidians of southern California, including the Channel Islands. Bull South Calif Acad Sci 70:114–124Google Scholar
  27. Folmer O, Black M, Hoeh W, Lutz R, Vrijenhoek R (1994) DNA primers for amplification of mitochondrial cytochrome c oxidase subunit I from diverse metazoan invertebrates. Mol Mar Biol Biotechnol 3:294–299PubMedGoogle Scholar
  28. Frankham R (2005) Stress and adaptation in conservation genetics. J Evol Biol 18:750–755CrossRefPubMedGoogle Scholar
  29. Fu Y-X (1997) Statistical tests of neutrality of mutations against population growth, hitchhiking and background selection. Genetics 147:915–925PubMedGoogle Scholar
  30. Gittenberger A (2007) Recent population expansions of non-native ascidians in the Netherlands. J Exp Mar Biol Ecol 342:122–126CrossRefGoogle Scholar
  31. Guindon S, Gascuel O (2003) A simple, fast, and accurate algorithm to estimate large phylogenies by maximum likelihood. Syst Biol 52:696–704CrossRefPubMedGoogle Scholar
  32. Holland BS (2000) Genetics of marine bioinvasions. Hydrobiologia 420:63–71CrossRefGoogle Scholar
  33. Jensen JL, Bohonak AJ, Kelley ST (2005) Isolation by distance, web service. BMC Genet 6:13CrossRefPubMedGoogle Scholar
  34. Jeschke JM, Strayer DL (2005) Invasion success of vertebrates in Europe and North America. Proc Natl Acad Sci 102:7198–7202CrossRefPubMedGoogle Scholar
  35. Keane T, Creevey C, Pentony M, Naughton T, Mclnerney J (2006) Assessment of methods for amino acid matrix selection and their use on empirical data shows that ad hoc assumptions for choice of matrix are not justified. BMC Evol Biol 6:29CrossRefPubMedGoogle Scholar
  36. Kolar CS, Lodge DM (2001) Progress in invasion biology: predicting invaders. Trends Ecol Evol 16:199–204CrossRefPubMedGoogle Scholar
  37. Kolbe JJ, Glor RE, Schettino LRG, Lara AC, Larson A, Losos JB (2004) Genetic variation increases during biological invasion by a Cuban lizard. Nature 431:177–181CrossRefPubMedGoogle Scholar
  38. Lambert G (2005) Ecology and natural history of the protochordates. Can J Zool 83:34–50CrossRefGoogle Scholar
  39. Lambert G (2007) Invasive sea squirts: a growing global problem. J Exp Mar Biol Ecol 342:3–4CrossRefGoogle Scholar
  40. Lambert CC, Lambert G (1998) Non-indigenous ascidians in southern California harbors and marinas. Mar Biol 130:675–688CrossRefGoogle Scholar
  41. Lambert CC, Lambert G (2003) Persistence and differential distribution of nonindigenous ascidians in harbors of the Southern California Bight. Mar Ecol Prog Ser 259:145–161CrossRefGoogle Scholar
  42. LeBlanc N, Davidson J, Tremblay R, McNiven M, Landry T (2007) The effect of anti-fouling treatments for the clubbed tunicate on the blue mussel, Mytilus edulis. Aquaculture 264:205–213CrossRefGoogle Scholar
  43. Lee CE (2002) Evolutionary genetics of invasive species. Trends Ecol Evol 17:386–391CrossRefGoogle Scholar
  44. LeGresley M, Martin J, McCurdy P, Thorpe B, Chang B (2008) Non-indigenous tunicate species in the Bay of Fundy, eastern Canada. ICES J Mar Sci 65:770–774CrossRefGoogle Scholar
  45. Lejeusne C, Chevaldonné P (2006) Brooding crustaceans in a highly fragmented habitat: the genetic structure of Mediterranean marine cave-dwelling mysid populations. Mol Ecol 15:4123–4140CrossRefPubMedGoogle Scholar
  46. Locke A, Hanson JM, Ellis KM, Thompson J, Rochette R (2007) Invasion of the southern Gulf of St. Lawrence by the clubbed tunicate (Styela clava Herdman): potential mechanisms for invasions of Prince Edward Island estuaries. J Exp Mar Biol Ecol 342:69–77CrossRefGoogle Scholar
  47. Lockwood JL, Cassey P, Blackburn T (2005) The role of propagule pressure in explaining species invasions. Trends Ecol Evol 20:223–228CrossRefPubMedGoogle Scholar
  48. Lopez-Legentil S, Turon X, Planes S (2006) Genetic structure of the star sea squirt, Botryllus schlosseri, introduced in southern European harbours. Mol Ecol 15:3957–3967CrossRefPubMedGoogle Scholar
  49. May GE, Gelembiuk GW, Panov VE, Orlova MI, Lee CE (2006) Molecular ecology of zebra mussel invasions. Mol Ecol 15:1021–1031CrossRefPubMedGoogle Scholar
  50. McCarthy A, Osman RW, Whitlatch RB (2007) Effects of temperature on growth rates of colonial ascidians: a comparison of Didemnum sp. to Botryllus schlosseri and Botrylloides violaceus. J Exp Mar Biol Ecol 342:172–174CrossRefGoogle Scholar
  51. Meenakshi VK, Senthamarai S (2006) First report on two species of ascidians to represent the genus Botryllus Gaertner, 1774 from Indian waters. J Mar Biol Assoc India 48:100–102Google Scholar
  52. Muirhead J, Gray D, Kelly D, Ellis S, Heath D, MacIsaac H (2008) Identifying the source of species invasions: sampling intensity vs. genetic diversity. Mol Ecol 17:431–449CrossRefGoogle Scholar
  53. Nei M (1987) Molecular evolutionary genetics. Columbia University Press, New YorkGoogle Scholar
  54. Pallas PS (1766) Elenchus zoophytorum sistens generum adumbrationes generaliores et specierum cognitarum succinctas descriptiones cum selectis auctorum synomymis. Varrentrapp, F, Frankfurt, p 539Google Scholar
  55. Panchal M, Beaumont MA (2007) The automation and evaluation of nested clade phylogeographic analysis. Evolution 61:1466–1480CrossRefPubMedGoogle Scholar
  56. Paz G, Douek J, Mo CQ, Goren M, Rinkevich B (2003) Genetic structure of Botryllus schlosseri (Tunicata) populations from the Mediterranean coast of Israel. Mar Ecol Prog Ser 250:153–162CrossRefGoogle Scholar
  57. Perez-Portela R, Turon X (2008) Cryptic divergence and strong population structure in the colonial invertebrate Pycnoclavella communis (Ascidiacea) inferred from molecular data. Zoology 111:163–178CrossRefPubMedGoogle Scholar
  58. Petit RJ (2007) The coup de grâce for the nested clade phylogeographic analysis? Mol Ecol 17:516–518PubMedGoogle Scholar
  59. Pfenninger M, Posada D (2002) Phylogeographic history of the snail Candidula unifasciata (Helicellinae, Stylommatophora): fragmentation, corridor migration, and secondary contact. Evolution 56:1776–1788PubMedGoogle Scholar
  60. Posada D, Crandall KA, Templeton AR (2000) GeoDis: a program for the cladistic nested analysis of the geographical distribution of genetic haplotypes. Mol Ecol 9:487–488CrossRefPubMedGoogle Scholar
  61. Ramos-Onsins SE, Rozas J (2002) Statistical properties of new neutrality tests against population growth. Mol Biol Evol 19:2092–2100PubMedGoogle Scholar
  62. Rice WR (1989) Analyzing tables of statistical tests. Evolution 43:223–225CrossRefGoogle Scholar
  63. Rius M, Pascual M, Turon X (2008) Phylogeography of the widespread marine invader Microcosmus squamiger (Ascidiacea) reveals high genetic diversity of introduced populations and non-independent colonizations. Divers Distrib 14:818–828CrossRefGoogle Scholar
  64. Rius M, Pineda MC, Turon X (2009) Population dynamics and life cycle of the introduced ascidian Microcosmus squamiger in the Mediterranean Sea. Biol Invasions 11:2181–2194CrossRefGoogle Scholar
  65. Rogers AD, Harpending H (1992) Population growth makes waves in the distribution of pairwise genetic differences. Mol Biol Evol 9:552–569PubMedGoogle Scholar
  66. Roman J (2006) Diluting the founder effect: cryptic invasions expand a marine invader’s range. Proc R Soc B Biol Sci 273:2453–2459CrossRefGoogle Scholar
  67. Roman J, Darling JA (2007) Paradox lost: genetic diversity and the success of aquatic invasions. Trends Ecol Evol 22:454–464CrossRefPubMedGoogle Scholar
  68. Rozas J, Sanchez-DelBarrio JC, Messeguer X, Rozas R (2003) DnaSP, DNA polymorphism analyses by the coalescent and other methods. Bioinformatics 19:2496–2497CrossRefPubMedGoogle Scholar
  69. Sakai AK, Allendorf FW, Holt JS, Lodge DM, Molofsky J, With KA, Baughman S, Cabin RJ, Cohen JE, Ellstrand NC, McCauley DE, O’Neil P, Parker IM, Thompson JN, Weller SG (2001) The population biology of invasive species. Annu Rev Ecol Syst 32:305–332CrossRefGoogle Scholar
  70. Schneider S, Excoffier L (1999) Estimation of past demographic parameters from the distribution of pairwise differences when the mutation rates vary among sites: application to human mitochondrial. Genetics 152:1079–1089PubMedGoogle Scholar
  71. Stoner DS, Ben-Shlomo R, Rinkevich B, Weissman IL (2002) Genetic variability of Botryllus schlosseri invasions to the east and west coasts of the USA. Mar Ecol Prog Ser 243:93–100CrossRefGoogle Scholar
  72. Suarez AV, Tsutsui ND, Holway DA (1999) Behavioral and genetic differentiation between native and introduced populations of the Argentine ant. Biol Invasions 1:43–53CrossRefGoogle Scholar
  73. Swofford DL (2001) PAUP*: phylogenetic analysis using parsimony (*and others methods). Sinauer, SunderlandGoogle Scholar
  74. Templeton AR (2004) Statistical phylogeography: methods of evaluating and minimizing inference errors. Mol Ecol 13:789–809CrossRefPubMedGoogle Scholar
  75. Templeton A (2008) Nested clade analysis: an extensively validated method for strong phylogeographic inference. Mol Ecol 17:1877–1880CrossRefPubMedGoogle Scholar
  76. Templeton AR (2009) Statistical hypothesis testing in intraspecific phylogeography: nested clade phylogeographical analysis vs. approximate Bayesian computation. Mol Ecol 18:319–331CrossRefPubMedGoogle Scholar
  77. Templeton AR, Boerwinkle E, Sing CF (1987) A cladistic analysis of phenotypic associations with haplotypes inferred from restriction endonuclease mapping. I. Basic theory and an analysis of alcohol dehydrogenase activity in Drosophila. Genetics 117:343–351PubMedGoogle Scholar
  78. Valentine PC, Collie JS, Reid RN, Asch RG, Guida VG, Blackwood DS (2007) The occurrence of the colonial ascidian Didemnum sp on Georges Bank gravel habitat—ecological observations and potential effects on groundfish and scallop fisheries. J Exp Mar Biol Ecol 342:179–181CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  • Christophe Lejeusne
    • 1
    • 2
  • Dan G. Bock
    • 1
  • Thomas W. Therriault
    • 3
  • Hugh J. MacIsaac
    • 1
  • Melania E. Cristescu
    • 1
  1. 1.Great Lakes Institute for Environmental ResearchUniversity of WindsorWindsorCanada
  2. 2.Wetland Ecology DepartmentEstación Biológica de Doñana-CSICSevillaSpain
  3. 3.Fisheries and Oceans Canada, Pacific Biological StationNanaimoCanada

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